✓ VERIFIED
May 16, 2026
not what I needed. description wasn't very clear but not worth sending back. oh well just have to be more careful next time
COMETIC
SKU: 68-9850
Cometic Evo Big Twin EST Gasket Kit - Harley Evolution Big Twin
$140.45
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About Cometic
Cometic Gasket manufactures multi-layer steel head gaskets and complete gasket kits in Concord, Ohio. On a built V-twin running higher compression or a big-bore kit, the MLS head gasket is what keeps the top end sealed — which is why Cometic is the default spec on so many engine builds.
When it's time for a full teardown or a refresh on your Evolution Big Twin, the Cometic EST Gasket Kit provides all the sealing components you need. This comprehensive kit ensures a complete and reliable rebuild, crucial for maintaining peak performance.
Why riders pick this
- Complete engine overhaul gasket kit
- MLS head gaskets for superior sealing
- Steel Viton-coated base gaskets
- Blue Viton valve stem seals included
- Designed for Evolution Big Twin engines
A proper engine rebuild starts with a complete and high-quality gasket kit. Cometic's EST (Extreme Sealing Technology) kit for Evolution Big Twin engines delivers exactly that, providing every gasket, seal, washer, and O-ring required for a thorough overhaul. Designed to handle the demands of performance V-twin motors, these gaskets offer superior sealing capabilities compared to stock components, preventing leaks and maintaining optimal compression.
Advanced Sealing for Performance Engines
- Includes MLS (Multi-Layer Steel) head gaskets for robust sealing
- Features steel Viton-coated base gaskets that resist heat and chemicals
- Equipped with blue Viton valve stem seals for enhanced durability
- Complete kit for a full engine overhaul, no missing components
Rebuild with Confidence
Whether you're doing a routine top-end refresh or a full bottom-end rebuild, using a comprehensive gasket kit like this from Cometic is essential for longevity and performance. The advanced materials and precision engineering ensure that your Evolution Big Twin engine will be sealed tight, ready for many more miles on the road. This kit is a smart choice for any rider or mechanic looking for reliability and peace of mind during an engine rebuild.
Specifications
- Brand: Cometic
- Manufacturer Part #: C9850
- Length: 8.9 in
- Width: 7.4 in
- Height: 2.1 in
- Weight: 0.8 lbs
Common questions
What engine models does this gasket kit fit?
This Cometic EST Gasket Kit is specifically designed for Evolution Big Twin engines found in various Harley-Davidson Touring, Softail, and Dyna models. Please confirm your specific year and model using our Shop by Bike tool.
What does EST stand for?
EST stands for Extreme Sealing Technology, which refers to Cometic's advanced gasket design and material system engineered for high-performance applications and reliable sealing.
Do I need any other gaskets or seals for a complete engine rebuild?
No, this Cometic Evo Big Twin EST Gasket Kit is a complete overhaul kit that includes every gasket, seal, washer, and O-ring needed for a full engine rebuild.
Ordering from Vtwinbikers
- Brand new, sourced through authorized US distribution — never used, never grey-market.
- Not sure it fits? Use Shop by Bike to filter by your year and model, or email us and we will confirm before you order.
- Harley-Davidson and Indian Motorcycle is all we do, so you are talking to people who ride what you ride.
| BRAND | Cometic |
| TYPE | Gaskets/Seals |
| SKU | 68-9850 |
| WEIGHT | 0.8 lb |
Please contact us to confirm fitment for your specific motorcycle, or check the product title for compatibility notes.
CUSTOMER REVIEWS
4.36
14 RATINGS
5★
11
4★
0
3★
1
2★
1
1★
1
✓ VERIFIED
Mar 8, 2026
Gasket
Working fine was for my brother's bike
✓ VERIFIED
Oct 25, 2024
Works Fine at a lower cost
I usually have an OEM from Harley Davidson, I have used this twice on my 04 Electraglide, no leaks or issues. At a much lower price.
✓ VERIFIED
Jun 8, 2024
A mediocre gasket
I didn’t use this gasket after removing the derby and seeing the Harley gasket that I removed. No comparison in quality. I ended up going to the local dealer and bought an O.E. gasket.
✓ VERIFIED
Jun 6, 2023
A good buy
The gasket fit nicely and no leaks so far . The fitment was spot on .
✓ VERIFIED
May 4, 2023
There is nothing on them indicating they are actually Cometic gaskets. Are they Substitutes?
